A First Assessment of Canopy Cover Loss in Germany's Forests after the 2018-2020 Drought Years

Central Europe was hit by several unusually strong periods of drought and heat between 2018 and 2020. These droughts affected forest ecosystems. Cascading effects with bark beetle infestations in spruce stands were fatal to vast forest areas in Germany. We present the first assessment of canopy cover loss in Germany for the period of January 2018-April 2021. Our approach makes use of dense Sentinel-2 and Landsat-8 time-series data. We computed the disturbance index (DI) from the tasseled cap components brightness, greenness, and wetness. Using quantiles, we generated monthly DI composites and calculated anomalies in a reference period (2017). From the resulting map, we calculated the canopy cover loss statistics for administrative entities. Our results show a canopy cover loss of 501,000 ha for Germany, with large regional differences. The losses were largest in central Germany and reached up to two-thirds of coniferous forest loss in some districts. Our map has high spatial (10 m) and temporal (monthly) resolution and can be updated at any time.

Automated summary

Central Europe experienced several severe droughts and heatwaves between 2018 and 2020, leading to significant impacts on forest ecosystems. In Germany, bark beetle infestations compounded the damage, resulting in extensive forest loss. This study utilized dense time-series data from Sentinel-2 and Landsat-8 to assess canopy cover loss in Germany from January 2018 to April 2021. The results revealed a total loss of 501,000 hectares, with varying levels of impact across different regions.